Snorkeling with turtles to places other than near the shipwreck & Carlisle Beach

We took an excursion to snorkel with the turtles a few years ago and although we saw many and it was fun, there were just too many people snorkeling in the same vicinity. Worried about getting kicked in head with someone's flipper or by a boat!

Any suggested spots to snorkel with boat or from beach in areas other than near the shipwreck and off Carlisle Beach?

Our guide told us we could also go to another beach, I think it was on Payne bay.